LTE: The next generation of mobile broadband for public safety
Public safety demand for data services grows daily and new spectrum and technology is needed to deliver mobile broadband operations.
Ready or not, the next generation of communication devices and the network that they will work on is right around the corner. Thanks in great part to all the cops shows, fact or fiction, where cops talk to firefighters all the time, under any conditions, on any frequency with streaming video in high definition, the public continues to think we have currently have this capability and training. While we all know the reality, it is important to know that the next generation of mobile broadband really is close at hand.
But before we talk about the next generation of public safety communications, I think it is important to understand where we came from, what we have accomplished, and where we are at in order to understand and better appreciate what is around the corner.
When I joined the Police Department in 1990, they had just transitioned to one of the first trunked radio systems in the National Capitol Region (NCR), most cars did not have a mobile radio and there were definitely no mobile data terminals in any of the cars.
Back then, officers would run vehicle registration checks, driver’s license checks and wanted checks on the primary dispatch channel of the police radio. If an officer had a vehicle with no tags, it meant running the vehicle identification number (VIN) using a phonetic alphabet. If an officer had four persons detained, it meant waiting in line until he checked the wanted status of all four persons; you guessed it — using the phonetic alphabet!
As my luck would have it that night, I was queued in line behind an officer with four persons stopped and in the middle of his wanted check (I will cut to the chase — no pun intended). The suspect ended up bailing out of his car; I engaged him in a foot pursuit through a neighborhood and ultimately caught him under a porch.
Once in handcuffs, I was able to get on the police radio and say that I had been in a chase and that I had a suspect in custody. That is just a small example of how congested and difficult it was to get on a police radio before mobile data computers/terminals came to support our operations.
The communications rate was slow and only in select areas of the City. But this was tremendous help because the early 90’s was the peak of crime in America and Alexandria, VA was certainly no exception. Getting on the police radio to run a registration or license check was next to impossible with the large volume of calls for service, foot and vehicle pursuits. At the time, CDPD vendors would brag about transmission rates of 19.2 kilobits per second (kbps), however, in the field under public safety conditions, the actual throughput was more like 12 kbps. This was barely enough bandwidth to get seven or eight lines of data to eight or nine cars roaming around in the City, but it certainly began to unclog our very congested police radio.
Nevertheless, this was a significant improvement because now this network supported more simultaneous users, the network coverage throughout the City had greatly increased and officers could access databases never before possible, such as CAD and RMS. This transition allowed us to be one of the first police department’s to complete incident reports in the field, send them to a supervisor for approval and if approved, to our records management section, all wirelessly.
And with the introduction of super tools like license plate readers on patrol cars, querying hundreds of license plates in minutes is now possible thanks to our current mobile broadband network, EV – DO. This is a true third generation mobile broadband network that provides typical download speeds of 600-1400kbps.
A big leap from 1xRTT speeds.
Undoubtedly the biggest advantages this network has given us are: sustainability of many more users, much better National network coverage and the ability to transmit high resolution color photos from the field to other patrol cars and Police Headquarters. No one knows the value of photos for police work more than cops and this is just another way we have become much more effective and efficient.
Remember the days of the radio BOLO (Be On the Look Out)? Officers would routinely broadcast a BOLO for a wanted person, a runaway, or an endangered elderly person. It was up to the receiver’s imagination to determine what that person might look like.
Today, our officers take digital photos of paper photos with their cameras then quickly download them onto their mobile data browser (MDB) and then send them out to others. This feature alone has allowed us to capture many more fugitives, runaways and endangered elderly persons than ever before. This capability was never possible with the CDPD or 1xRTT networks.
When our officers canvass a crime scene, identifying and collecting video sources is a big and first part of their investigation. The demand for video in the public safety environment is growing rapidly and will continue to grow. This is fueled in part by the recognition of the value that video can play in solving crimes or locating wanted persons, but also in part by the advancement and availability of digital video technology. Just look around and you will see video surveillance almost everywhere. Video in a mobile environment is the next frontier and it is knocking on our door.
This is where LTE comes to the door. Long Term Evolution (LTE) is the latest standard in mobile broadband, a fourth generation technology. With an average eight Megabytes per second (Mbps) download, and four Mbps upload, transmitting video to and from a patrol car can be accomplished with ease.
Like with any new technology, one of the common challenges is to make sure public safety practitioners are given a solid foundation of fact and information to become an educated consumer. One of the dangers is to assume that technologies that provide the same type of function (communications, e.g.) can be understood through the same prism of the older, legacy technology. With LTE as opposed to Land Mobile Radio (LMR), it requires a fundamental shift in thinking and understanding. Not just in how the technology works, but how to design, procure and use it.
As the old saying goes, this is not about using LTE to pave cow paths — this is a totally new form of communications and capabilities.
The promise of LTE is to unify the public safety environment and provide a single, common experience – whether fixed or mobile and regardless of device. LTE is a flat, open standards-based, all IP architecture. Currently, public safety operations are organized around fixed and mobile environments. In the fixed environments you will find headquarters and operations that involve day-to-day and long range activities. There are also the emergency operations and communications functions (very tactical – measured in seconds), investigations, training and other related functions that take place in a fixed location.
These fixed locations are hooked to a wired network that provide more bandwidth and access to information than what is available to field personnel. In the field, many applications have mobile clients that are essentially stripped-down versions of the original application. These less-capable versions provide limited access to information, media, photographs and video depending on the coverage with commercial service providers, if an agency has any mobile data services at all. First responders, whose own personal safety is at greater risk, have the least access to the information and data needed to do their job at the point where it is needed most — the tip of the spear.
Here in Alexandria, we recently participated in and completed what I think was the first field trial in North America using a defined LTE network with Alcatel – Lucent. Using a police vehicle and paramedic unit with trained personnel, we staged a scenario that required robust voice, data and video at a major fire scene. Through this field trial, not only were we able to deliver voice, data and multiple simultaneous video streams through one network, but the quality of the video had higher resolution than my high definition (HD) television at home. For the first time, I was able to witness voice, data, and video, all on one network with the clarity of an HD television in a mobile broadband environment.
Public safety has clearly identified LTE as our next generation solution for mobile broadband to address the challenges of a very demanding environment – voice, data, video, interoperability and situational awareness all bundled in one network.
Land Mobile Radio and LTE
But before we talk about the future and in order to validate previous statements, it is important to understand the past and what we (public safety and the private sector) have accomplished thus far.
The Land Mobile Radio (LMR) of today, at a basic level, is a narrowband, circuit-switched network. Originally, the channels were 25 kHz (analog / conventional), which were halved to 12.5 kHz and now are being halved again to 6.25 kHz (trunked / digital). What this means is the channels for voice are getting smaller and smaller, and wide area data may be able to get 10 kilobits per second (kbps). In one minute at 10 kbps, you’d be lucky to download one 75 kilobyte (KB) file – a small thumbnail picture.
In comparison, with LTE, at peak user data rates of 31.7 Mbps (in 2x5 MHz configuration — the current allocation of spectrum to public safety in 700MHz), in the same minute while using a LTE network; you could download a 237 Megabyte (MB) file. In essence, LTE will allow you to complete a Voice Over IP (VoIP) telephone call, stream video in and out of the vehicle and send car-to-car data messages – at the same time on the same device!
Before you start to dismiss my credibility or call me insane, I am not saying public safety is ready to transition LMR to LTE. There is currently lots of discussion focused on whether or not LTE can be mission-critical in the way LMR operates today. It is absolutely not there yet. And there is no doubt public safety needs the reliability and assurance that their communications will be there – that it just works when and where needed. The initial deployments of LTE will be data only. The difference between LTE and LMR is that LTE can handle voice, data, video and multimedia services on the same network. Separate networks are not needed. As LTE progresses, it will provide non-mission critical voice and data within 2 years, with the goal of achieving mission critical voice and data by the end of 5 years.
Regardless of how much the technology changes, the first responder wants the same reliability and experience with voice in the field. It is expected that Push-To-Talk (PTT) will be available in LTE the same way it is today with LMR. There will be talk-around, the ability to support P25 clients on an LTE device, get data, video, car-to-car messaging, full access to applications and more. Devices like laptop modems, trunk-mounted modems and routers, rugged handhelds, or the equivalent of PTT radio devices that operate on LTE are coming.
As major commercial wireless service providers roll out their next generation LTE networks (4G), public safety can benefit from the experience and lessons of the telecommunications industry as they look to use this technology for mission-related work.
The Long Road Ahead
Nine public-safety associations commonly referred to as “The Big 9” (Association of Public-Safety Communications Officials (APCO) International, the International Association of Chiefs of Police, the International Association of Fire Chiefs, the National Sheriffs’ Association, the Major Cities Chiefs Association, the Major County Sheriffs’ Association, the Metropolitan Fire Chiefs Association, the National Emergency Management Association and the National Association of EMS Officials) and seven state and local government organizations, commonly referred to as “The Big 7” (National Governors Association, the National Conference of State Legislatures, the Council of State Governments, the National Association of Counties, the National League of Cities, the U.S. Conference of Mayors and the International City/County Management Association) have asked Congress to reallocate the 700 MHz D-Block for the proposed nationwide broadband network for first responders.
These public-safety and state and local government organizations have been seeking a D-Block reallocation so that this spectrum can be used with adjacent public-safety broadband spectrum that is currently licensed to the Public Safety Spectrum Trust (PSST). In the national broadband plan, the Federal Communications Commission (FCC) recommends auctioning the D-Block, citing the need for more spectrum for commercial mobile services.
And just like our current public safety technology, our teenage sons and daughters will continue to have more cutting edge technology than the public safety community. But there is a good reason for that: standards, specifications, and redundancy. No one gets hurt when my daughter’s Droid telephone doesn’t work while out at the mall trying to text, talk and send video to her friends. In our world, our lives and the lives of the people we serve and protect are at stake.
The most important goals of deploying any mobile data solution are to create more capacity on the police radio for the real emergencies and to make law enforcement personnel more effective and efficient by providing them with unlimited data and video. Currently our law enforcement personnel work with their hands tied behind their back when dealing with criminal elements with limited access to criminal justice databases, especially those that contain photographs.
It is often said that no one likes change and the law enforcement culture is probably the largest group of “change haters”, however, we have witnessed progressive transitions from second generation technologies to third generation and we could not imagine going back in time. But there is lots of work yet to be done before public safety can begin to embrace this new technology called LTE. But rest assured, when these networks are built, they will come. So ready or not, here it comes!
|Back to previous page|